Popes are human beings, and products of their culture.
Is it possible that men like Pius X, now a saint, knew of clerical abuse and did nothing? Absolutely, but he was simply ignorant of the hideousness of the act and its effect on the victims.
But, that was a different time, when the Church crushed common people under the burden of anathemas that, today, make no sense and have no applicability.
It also exalted clerics to positions of pre-eminence that they did not deserve, and should not have had, given that they were to be followers of Him who had nowhere to lay His Head.
Understand, my Church has much to answer for. But, men are fallible, which is why we fix our eyes on the Christ who pulls every man to grow outside of himself, to get out of his comfort zone, to become Christ himself.
The Church is being put through fire because it deserves it.
Christ, however, is constant, and His Word that He will be with His Church is reassuring.